Coating for aqueous inkjet transfer
A coating composition for an image transfer member in an aqueous ink imaging system is disclosed that comprises a hydrophilic composition and a surfactant. The hydrophilic composition can be a starch-based composition.
1. A coating composition for an image transfer member in an aqueous ink imaging system in which the aqueous ink includes a colorant in a liquid solvent, comprising:
a hydrophilic composition including an absorption agent in a liquid carrier, the absorption agent adapted to absorb the solvent in the aqueous ink and to be substantially impermeable to the colorant in the aqueous ink when the hydrophilic composition is dried; and
a surfactant.
2. The coating composition of claim 1 , wherein the absorption agent is adapted to swell in response to absorption of the liquid solvent from the aqueous ink.
3. The coating composition of claim 1 , wherein the liquid carrier is water.
4. The coating composition of claim 1 , wherein the absorption agent includes a starch.
5. The coating composition of claim 4 , wherein the starch includes a starch selected from the group including corn starch, potato starch, rice starch, wheat flour, rice flour and corn flour.
6. The coating composition of claim 4 , wherein the starch is a starch consisting of predominantly amylopectin.
7. The coating composition of claim 4 , wherein the starch is a waxy starch.
8. The coating composition of claim 7 , wherein the starch includes a starch selected from the group including waxy corn starch, waxy potato starch, and glutinous rice starch.
9. The coating composition of claim 1 , further comprising a biocide composition.
10. The coating composition of claim 1 , wherein the surfactant is a silicone-based polymer composition.
11. An aqueous ink transfer process comprising:
coating the surface of an image transfer member (ITM) with a coating composition to a first thickness, the coating composition including a hydrophilic composition and a surfactant, wherein the hydrophilic composition includes an absorption agent in a liquid carrier, the absorption agent adapted to absorb the solvent in the aqueous ink;
partially drying the coating composition to a reduced second thickness;
applying aqueous ink onto the coating composition in which the aqueous ink includes a colorant in a liquid solvent;
swelling the coating composition by absorbing water from the ink;
partially drying the ink; and
transferring the ink onto a substrate.
12. The aqueous ink transfer process of claim 11 , wherein the first thickness is between 1 μm and 10 μm.
13. The aqueous ink transfer process of claim 12 wherein the second thickness of between 0.1 μm and 1 μm.
14. The aqueous ink transfer process of claim 11 , wherein the surface of the ITM has a low surface energy.
15. The aqueous ink transfer process of claim 11 , wherein the step of applying aqueous ink includes applying the ink in an imagewise manner.
16. The aqueous ink transfer process of claim 11 , wherein the absorption agent includes a starch.
17. The aqueous ink transfer process of claim 16 , wherein the starch is a starch consisting of predominantly amylopectin.
18. The aqueous ink transfer process of claim 16 , wherein the starch includes a starch selected from the group including corn starch, potato starch, rice starch, wheat flour, rice flour and corn flour.
19. An aqueous ink transfer process comprising:
coating the surface of an image transfer member (ITM) with a coating composition, the coating composition including a hydrophilic composition and a surfactant, wherein the hydrophilic composition includes an absorption agent in a liquid carrier, the absorption agent adapted to absorb the solvent in the aqueous ink;
applying aqueous ink onto the coating composition in which the aqueous ink includes a colorant in a liquid solvent;
after applying the ink, reducing the adherence of the coating composition to the surface of the ITM;
partially drying the ink; and
transferring the ink onto a substrate.
20. The aqueous ink transfer process of claim 19 , wherein the surface of the ITM has a low surface energy.